JP7577876B2 - Ceramic Susceptor - Google Patents

Description

The present invention relates to a ceramic susceptor, and in particular to a ceramic susceptor in which air is pumped through the internal space of the shaft.

Generally, semiconductor devices or display devices are manufactured by sequentially stacking a plurality of thin film layers, including dielectric layers and metal layers, on a glass substrate, a flexible substrate, or a semiconductor wafer substrate, and then patterning the layers. These thin film layers are sequentially deposited on the substrate by a chemical vapor deposition (CVD) process or a physical vapor deposition (PVD) process. The CVD process includes a low pressure chemical vapor deposition (LPCVD) process, a plasma enhanced chemical vapor deposition (PECVD) process, a metal organic chemical vapor deposition (MOCVD) process, etc.

In such CVD and PVD equipment, a ceramic susceptor is disposed to support a glass substrate, a flexible substrate, a semiconductor wafer substrate, etc. and to perform heat treatment, etc. The ceramic susceptor may be installed in the CVD and PVD equipment and used to heat the substrate in a heat treatment process, etc. In addition, the ceramic susceptor may be equipped with a radio frequency (RF) electrode and used to generate plasma in an etching process of a thin film layer formed on a semiconductor wafer substrate, etc.

Figure 1A is a schematic cross-sectional view showing a conventional ceramic susceptor.

First, as shown in FIG. 1A, the conventional ceramic susceptor includes an insulating plate 10 coupled to a shaft 20, and the insulating plate 10 includes a heating element 12, such as a mesh-shaped element, arranged in a ceramic material. The heating element 12 is connected to a connecting rod 22 and receives power from an external power source to the mount 30. In addition, the conventional ceramic susceptor pumps air through a flow path 31 that passes through the insulating plate 10, the shaft 20, and the mount 30 to fix a substrate 11, such as a semiconductor wafer, by using a vacuum chuck function during a semiconductor process. In particular, the flow path 31 is formed inside the longitudinal sidewall of the shaft 20. However, in the conventional ceramic susceptor, it is difficult to align the flow path 31 in the process of bonding the insulating plate 10, the shaft 20, and the mount 30 after they are individually manufactured. Therefore, the production yield of the conventional ceramic susceptor is reduced, and as a result, there is a problem in that the processing cost increases.

Moreover, in such conventional ceramic susceptors, the cross-sectional area of the shaft 20 must be made large in order to process the through-flow passage 31 in the side wall of the shaft 20, which increases the problem of increased heat loss. In addition, as shown in Figures 1B and 1C, the heating element 12 as well as the high-frequency electrode (not shown) arranged other than the heating element 12 must be bent in order to avoid the hole 33 through which the flow passage 31 in the side wall of the shaft 20 reaches the upper surface of the insulating plate 10 where the groove 15 is located, but this also causes problems of heat loss and reduced temperature uniformity in the surrounding zone AA.

Korean Patent Application No. 10-2009-0020821 (March 11, 2009) Korean Patent Application No. 10-2017-0168278 (December 8, 2017) International Patent Application WO1999/56307 (November 4, 1999)

The present invention has been devised to solve the above problems, and the object of the present invention is to provide a ceramic susceptor that allows air pumping through the internal space of the shaft, thereby enabling a vacuum chuck function and a purge function, so that the alignment and joining of parts can be made easier, thereby improving yields and reducing processing costs, and that allows such vacuum chuck/purge functions to be used simultaneously with an electrostatic chuck.

In addition, the connecting rod for supplying power to the internal space of the shaft can be made of a single material without an intermediate layer (KOVAR) to prevent oxidation, thereby providing a ceramic susceptor that can reduce electrical resistance and the effects of shear stress.

First, to summarize the features of the present invention, a ceramic susceptor according to one aspect of the present invention for achieving the above object includes an insulating plate on which an electrode is disposed; a shaft having one end connected to the insulating plate; a power supply rod connected to the electrode and extending to pass through the internal space of the shaft; and a separator plate coupled to the other end of the shaft and sealing the internal space of the shaft, the insulating plate including a first through passage penetrating between an upper surface and a lower surface to communicate with the internal space of the shaft, and the first through passage can be used to perform a vacuum chuck function and/or a purge function.

The ceramic susceptor may further include a mount connected to the lower portion of the shaft and including a second through passage that connects the interior space of the shaft to the outside.

By maintaining the first through passage at a negative pressure lower than atmospheric pressure, the substrate placed on the insulating plate can be adsorbed.

The purging function can be performed by maintaining a positive pressure higher than atmospheric pressure through the first through passage.

The electrode may be a heating element, and the ceramic susceptor may further include a plasma generating electrode disposed within the insulating plate and spaced apart from the electrode.

The insulating plate includes a second electrode that is disposed apart from the electrode and is used to chuck and dechuck a substrate disposed on the insulating plate. The second electrode is used to hold the substrate in a chucked state, while a positive pressure is maintained through the first through-passage, higher than atmospheric pressure, thereby simultaneously performing a purge function.

The ceramic susceptor may further include a connector embedded in the insulating plate and electrically connected to the electrode, and the power supply rod may be brazed to the connector with a conductive filler.

The power supply rod may be extended as a single rod through the interior space of the shaft, contacting the connector, and through a mount at the bottom of the shaft.

The connector and the power supply rod may be made of the same material.

The electrode may be a heating element, an electrode for generating plasma, or a chuck electrode for electrostatic chuck function.

The electrode may be a heating element, and the ceramic susceptor may further include a chuck electrode for electrostatic chuck function, disposed within the insulating plate and spaced apart from the electrode.

When performing a vacuum chuck function using the first through passage, an electrostatic chuck function can also be performed using the electrode.

The ceramic susceptor of the present invention has the advantage that air pumping for substrate chucking is performed through the internal space of the shaft, making it easier to align and join parts, thereby improving yields and reducing processing costs.

In addition, the present invention does not require the machining of through holes in the side walls of the shaft, which allows the shaft cross-sectional area to be made smaller, resulting in reduced heat loss compared to the prior art. Also, since the chucking or purging function can be achieved using the through passage on the central side, there is no need to bend the built-in heating element or electrodes to avoid the through passage on the central side. This has the effect of improving temperature uniformity in the zone around the through passage (BB in FIG. 2C) compared to the prior art.

In addition, the connecting rod for supplying power to the shaft internal space can be made of a single material without an intermediate layer (KOVAR) for stress buffering, which reduces the electrical resistance of the connecting rod and reduces the occurrence of cracks or arching due to shear stress.

In addition, the vacuum chuck function is realized using the internal space at the center of the shaft, and the electrostatic chuck function is simultaneously used by the chuck electrode. This not only complements the chucking force of the vacuum chuck function when the chucking force of the vacuum chuck function is weak in the low-pressure atmosphere of the semiconductor processing chamber using the electrostatic chuck electrode, and complements the chucking force when the chucking force of the electrostatic chuck electrode is weak in the high-temperature atmosphere of the semiconductor processing chamber using the vacuum chuck function, but also reduces the thermal conductivity of the shaft at high temperatures due to the vacuum in the internal space of the shaft (vacuum reduces thermal conductivity) and reduces oxidation problems of the power supply rod inside the shaft (vacuum also reduces oxidation problems).

The accompanying drawings, which are included as part of the detailed description to aid in understanding the present invention, provide examples of the present invention and, together with the detailed description, explain the technical concept of the present invention.

FIG. 1 is a schematic cross-sectional view showing a conventional ceramic susceptor. 1B is an example of a heating element pattern when the ceramic susceptor of FIG. 1A is viewed from above. FIG. 1B is a top view of the ceramic susceptor of FIG. 1A, showing the upper surface of an insulating plate and a heating element thereunder superimposed thereon. 1 is a schematic cross-sectional view showing a ceramic susceptor according to an embodiment of the present invention. 2B is an example of a heating element pattern when the ceramic susceptor of FIG. 2A is viewed from above. 2B is a top view of the ceramic susceptor of FIG. 2A, showing the upper surface of an insulating plate and the heating element thereunder superimposed thereon. FIG. 2 is a cross-sectional view showing a connecting rod joint portion according to a first embodiment of the ceramic susceptor of the present invention. FIG. 4 is a cross-sectional view showing a connecting rod joint portion according to a second embodiment of the ceramic susceptor of the present invention.

The present invention will be described in detail below with reference to the accompanying drawings. In each drawing, the same components are denoted by the same reference numerals as much as possible. Also, detailed descriptions of already known functions and/or configurations will be omitted. The contents disclosed below will focus on the parts necessary for understanding the operation of various embodiments, and descriptions of elements that may make the gist of the description unclear will be omitted. Also, some components in the drawings may be exaggerated, omitted, or illustrated in outline. The size of each component does not entirely reflect the actual size, and therefore the contents described herein are not limited by the relative sizes or spacing of the components depicted in each drawing.

When describing the embodiments of the present invention, if it is determined that a detailed description of a known technology related to the present invention may make the gist of the present invention unclear, the detailed description will be omitted. The terms described below are defined in consideration of the functions in the present invention, and may be changed according to the intention or practice of the user or operator. Therefore, the definitions should be based on the entire contents of this specification. The terms used in the detailed description are merely for the purpose of describing the embodiments of the present invention, and should not be limiting in any way. Unless otherwise specified, expressions in the singular form include the plural form. In this description, expressions such as "include" or "comprise" are intended to indicate certain characteristics, numbers, steps, operations, elements, parts thereof, or combinations thereof, and should not be interpreted as excluding the presence or possibility of one or more characteristics, numbers, steps, operations, elements, parts thereof, or combinations other than those described.

Note that terms such as first and second may be used to describe various components, but these terms do not limit the various components, and are used only to distinguish one component from another.

Figure 2A is a schematic cross-sectional view showing a ceramic susceptor according to one embodiment of the present invention.

First, referring to FIG. 2A, a ceramic susceptor 100 according to an embodiment of the present invention includes an insulating plate 110, a shaft 120, and a mount 140. The insulating plate 110, the shaft 120, and the mount 140 are connected in sequence, and a separator 130 formed at the longitudinal end of the shaft 120 may be included between the shaft 120 and the mount 140 to separate the internal spaces from each other.

The ceramic susceptor 100 according to one embodiment of the present invention has a vacuum chuck structure that supports substrates 11 to be processed for various purposes, such as semiconductor wafers, glass substrates, flexible substrates, etc., using an air pump 500.

To this end, the insulating plate 110 is configured to have a heating element (electrode) 114 disposed (embedded) between the ceramic material, and may further be configured to have another electrode 112 disposed (embedded) at a predetermined interval from the heating element 114, as the case may be. The insulating plate 110 is configured to stably support a substrate to be processed, and to perform various semiconductor processes such as heating using the heating element 114 and/or supporting the substrate using the electrode 112, or a plasma enhanced chemical vapor deposition process or a dry etching process using plasma. The insulating plate 110 may be formed as a plate-like structure having a predetermined shape. For example, the insulating plate 110 may be formed as a circular plate-like structure, but is not necessarily limited thereto. Here, the ceramic material may be _{at least one of Al2O3, Y2O3, Al2O3/Y2O3 , ZrO2 , AlC ( Autoclaved lightweight concrete} ), TiN, AlN, TiC, MgO, _CaO , _CeO2 , _TiO2 , _BxCy , BN, _SiO2 , SiC, YAG, Mullite, and _AlF3 , and preferably aluminum nitride (AlN). Powder of the ceramic material may be molded and sintered to form the insulating plate 110, and each ceramic powder for this purpose may selectively contain about 0.1 to 10%, preferably about 1 to 5%, of yttrium oxide powder.

The heating element (electrode) 114 may be formed in the form of a plate coil or flat plate using a heating wire (or resistance wire). The heating element 114 may also be formed in a multi-layer structure for precise temperature control. The heating element 114 is connected to a power source provided to the separate heating element 114 through the connecting rods 121 and 122 to receive power, and can function to heat the substrate 11 to be processed on the insulating plate 110 to a predetermined temperature in order to heat the substrate in a semiconductor process, or to perform a deposition process and an etching process. The connecting rods 121 and 122 pass through the internal space of the shaft 120, pass through the separator 130, and extend to the outside through the mount 140.

The electrode 112 may be made of tungsten (W), molybdenum (Mo), silver (Ag), gold (Au), niobium (Nb), titanium (Ti), aluminum nitride (AlN), or an alloy thereof, and may be preferably made of molybdenum (Mo). The electrode 112 may be connected to a power terminal (e.g., ground) through another connecting rod (not shown). The connecting rod (not shown) for the electrode 112 may also extend through the internal space of the shaft 120, through the separator 130, and through the mount 140 to the outside. For example, the electrode 112 may be used as a chuck electrode for an electrostatic chuck function for supporting the substrate 11 placed on the insulating plate 110, or as a plasma generation electrode for a plasma generation function for processes such as plasma enhanced chemical vapor deposition or dry etching in a RIE (Reactive Ion Etch) device.

The shaft 120 has a pipe shape having a through hole, and is coupled to the lower surface of the insulating plate 110. The shaft 120 may be formed of the same ceramic material as the insulating plate 100 and coupled thereto. Here, the ceramic material may be at least one of _Al2O3 , _{Y2O3 , Al2O3} / _Y2O3 , _ZrO2 , _AlC ( _autoclaved lightweight concrete), _TiN , AlN, TiC, _MgO , CaO, _CeO2 , _TiO2 , _BxCy , BN, _SiO2 , SiC, YAG, mullite, and _AlF3 , and may be preferably aluminum nitride (AlN). The ceramic powder may be molded and sintered to form the shaft 120, and each ceramic powder may optionally contain about 0.1 to 10%, preferably about 1 to 5%, of yttrium oxide powder.

The shaft 120 may be joined to the insulating plate 110 with a joining material 125 such as ceramic paste. In some cases, the shaft 120 may be mechanically joined to the insulating plate 110 with bolts, nuts, etc. The rods (121, 122, etc.) that supply power to the electrodes 112 and/or the heating element 114 are housed through an internal space penetrating the shaft 120, and these extend outward through a mount 140 that is in a sealed form (e.g., a rigid body or a member having a hollow).

As shown in FIG. 2A, the mount 140 is connected to the longitudinal end of the shaft 120. The mount 140 may be mechanically connected to the shaft 120 by sandwiching the separator 130 formed at the longitudinal end of the shaft 120. The connection between the shaft 120 and the separator 130 may be mechanically connected using bolts, nuts, etc. Also, the connection between the shaft 120 and the separator 130 and the upper part of the mount 140 may be mechanically connected using bolts, nuts, etc., and may be sealed so as to be completely sealed. The periphery of the through holes of the separator 130 for the connecting rods (121, 122, etc.) passing through the separator 130 may be sealed without gaps using a paste of the ceramic material as described above. The upper part of the mount 140 may be tightened so as to wrap around the separator 130. Between the top of the mount 140 and the separator 130 or between the top of the mount 140 and the shaft 120, i.e., the joint between the shaft 120 with the separator 130 and the mount 140, may be sealed without gaps with a paste of the ceramic material as described above.

The connecting mount 140 and the separator 130 may be made of a metal material such as aluminum (Al) or may be made of a ceramic material such as the above. That is, the ceramic material may be at least one of _Al2O3 , _{Y2O3 , Al2O3} / _Y2O3 , _ZrO2 , AlC (autoclaved lightweight concrete), _TiN , AlN, TiC, MgO, CaO, _CeO2 , _TiO2 , _BxCy , BN _{, SiO2} , SiC, _YAG , mullite _, and _AlF3 , and is preferably aluminum nitride (AlN). The ceramic powder may be molded and sintered to form the shaft 120, and each ceramic powder may optionally contain about 0.1 to 10%, preferably about 1 to 5%, of yttrium oxide powder.

In one embodiment of the present invention, the ceramic susceptor 100 functions as a vacuum chuck by pumping air through the inner space of the shaft 120, and can easily align and join the air flow paths of the components such as the insulating plate 110, the shaft 120, and the mount 140, thereby improving yield and reducing processing costs. In addition, in the present invention, the inner space of the shaft 120 is maintained at a vacuum (negative pressure) lower than atmospheric pressure, so that oxidation of the connecting rods 121 and 122 in the inner space of the shaft 120 is prevented. Therefore, the connecting rods 121 and 122 can be embodied as a single rod rather than a double-connected structure 51 and 52 (see FIG. 3), and the material of the connecting rods 121 and 122 can be made of Mo, which is the same as the material of the connector 41 (see FIG. 3 and FIG. 4) electrically connected to the heating element 114 (or other electrode 112) of the insulating plate 110. In other words, by making it possible to form the connecting rods 121 and 122 from a single material such as Mo without an intermediate layer 51 (KOVAR) (see FIG. 3) for stress buffering, it is possible to reduce the electrical resistance of the connecting rods 121 and 122 and reduce the occurrence of cracks or arching due to shear stress.

In one embodiment of the present invention, the ceramic susceptor 100 uses the internal space of the shaft 120 to achieve a vacuum chuck function, and at the same time, the electrode 112 of the chuck electrode also enables an electrostatic chuck function.

For this purpose, the insulating plate 110 includes a first through passage 91 for communication between the upper surface on which the substrate 11 is placed and the internal space of the shaft 120 so that air is pumped through the internal space of the shaft 120 to function as a vacuum chuck. The first through passage 91 is formed to penetrate between the upper surface and the lower surface near the center of the insulating plate 110, and the upper surface on which the substrate 11 is placed and the internal space of the shaft 120 are fluidically connected by the first through passage 91. In addition, the mount 140 includes a second through passage 92 that communicates the internal space of the shaft 120 with the outside so that air (vacuum pumping) is pumped through the internal space of the shaft 120 to function as a vacuum chuck. When the air pump 500 is connected to the second through-passage 92 and performs an air pumping operation, air is pumped through the first through-passage 91, the internal space of the shaft 120, and the second through-passage 92, and the internal space of the shaft 120 and the first through-passage 91 are maintained at a negative pressure lower than atmospheric pressure, thereby adsorbing the substrate 11 disposed on the insulating plate 110. In this manner, when performing a vacuum chuck function using the first through-passage 91, it is possible to further perform an electrostatic chuck function by using the electrode 112 as an electrostatic chuck electrode. When the electrostatic chuck function is used simultaneously by applying power for chucking and dechucking using the electrostatic chuck electrode 112 together with the vacuum chuck function using the first through passage 91, the chucking force can be supplemented using the electrostatic chuck electrode 112 when the chucking force of the vacuum chuck function is weak in the low pressure atmosphere in the semiconductor processing chamber, and when the chucking force of the electrostatic chuck electrode 112 is weak in the high temperature atmosphere in the semiconductor processing chamber, the vacuum chuck function can be used to supplement the chucking force. In addition, the thermal conductivity of the shaft 120 can be reduced by the vacuum in the internal space of the shaft 120 at high temperatures (vacuum reduces thermal conductivity), and the oxidation problem of the power supply rod inside the shaft 120 can be reduced (vacuum also reduces oxidation problems).

The inside of the mount 140 may be in the form of a rigid body or a member having a hollow. If the mount 140 is a rigid body, the mount 140 may be provided with a through hole for passing the connecting rods 121 and 122 and a through hole for forming the second through passage 92. If the mount 140 is in the form of a member having a hollow, the through hole for passing the connecting rods 121 and 122 may be provided between the upper and lower ends of the mount 140, and a pipe-shaped member (e.g., metal or ceramic material) for the second through passage 92 may be provided between the upper and lower ends of the mount 140.

Figure 2B shows an example of the pattern of the heating element 114 when the ceramic susceptor 100 in Figure 2A is viewed from above.

Figure 2C is a top view of the ceramic susceptor 100 in Figure 2A, showing the upper surface of the insulating plate 110 and the heating element 114 underneath it.

Referring to FIG. 2B and FIG. 2C, the ceramic susceptor 100 of the present invention does not require a through hole to be machined in the side wall of the shaft 120, which allows the cross-sectional area of the shaft 120 to be made small. Therefore, the ceramic susceptor 100 of the present invention can reduce heat loss compared to the conventional technology (see FIG. 1A to FIG. 1C), can realize a chucking or purging function using the through passage 91 on the central side, and does not require the built-in heating element 114 or electrode 112 to be bent to avoid the through passage on the central side, which has the effect of improving the temperature uniformity in the zone around the through passage 91 (BB in FIG. 2C) compared to the conventional technology.

The ceramic susceptor 100 of the present invention as described above may be installed in the chamber of a CVD or PVD apparatus and used for heating using the heating element 114 and/or supporting the substrate using the electrode 112, or for plasma-enhanced chemical vapor deposition processes or dry etching processes using plasma. As described above, the ceramic susceptor 100 of the present invention can chuck and dechuck the substrate 11 by negative pressure air pumping through the first through passage 91, the internal space of the shaft 120, and the second through passage 92, and at this time, the insulating plate 110 is configured to stably support the substrate to be processed and perform various semiconductor processes such as heating using the heating element 114 and/or supporting the substrate using the electrode 112, or for plasma-enhanced chemical vapor deposition processes or dry etching processes using plasma.

Meanwhile, the ceramic susceptor 100 of the present invention can perform not only chucking and dechucking of the substrate 11 using the first through passage 91, etc., but also a purge function by maintaining the first through passage 91 at a pressure higher than atmospheric pressure through positive pressure air pumping through the first through passage 91, the internal space of the shaft 120, and the second through passage 92. At this time, the air pump 500 can perform pumping to inject air at a predetermined pressure higher than atmospheric pressure through the second through passage 92.

For example, purging can be performed by blowing air containing a specific gas (e.g., nitrogen gas, or an inert gas such as He or Ar) into the chamber of the CVD or PVD device described above through the first through passage 91 using positive pressure air pumping.

This can blow and remove particles accumulated in pockets, especially grooves 15, on the upper surface of the insulating plate 110 in the chamber. This purging function is preferably performed after chucking the substrate 11 on the upper surface of the insulating plate 110, but may be performed even if there is no substrate 11 on the upper surface of the insulating plate 110, if necessary. However, during this purging function, an electrode disposed in the insulating plate 110, i.e., the electrode 112 as shown in FIG. 2A, may be used to chuck and dechuck the substrate 11 placed on the upper surface of the plate 110 in addition to the heating element 114. That is, the electrode 112 may be a high-frequency electrode disposed to receive a power supply for generating plasma as described above, or may be an electrostatic chuck electrode (or a chuck electrode) disposed to receive a power supply for chucking and dechucking the substrate 11. In addition, the electrode 112 may function as an electrostatic chuck electrode as it is, and an additional chuck electrode may be formed at a predetermined distance from the electrode 112 to receive power for chucking and dechucking the substrate 11. That is, the heating element 114, the electrode 112, and the additional electrode for chucking and dechucking the substrate 11 may be formed in different layers at a predetermined distance from each other within the insulating plate 110.

Figure 3 is a cross-sectional view showing the connection portion of the connecting rods 121, 122 in the first embodiment of the ceramic susceptor 100 of the present invention.

Referring to FIG. 3, the connecting rods 121, 122 may be electrically connected to the connector 41 embedded in the insulating plate 110 so as to be electrically connected to the heating element 114 (or the electrode 112). Here, the connecting rods 121, 122 are configured in a double-connected structure, i.e., a first rod 51 and a second rod 52, through a support eyelet 70 coupled to a thread formed on a part of the inner circumferential surface of a predetermined opening of the insulating plate 110.

Here, the connector 41, the connecting rods 121 and 122, and the support eyelet 70 may be made of a conductive material, for example, tungsten (W), molybdenum (Mo), silver (Ag), nickel (Ni), gold (Au), niobium (Nb), titanium (Ti), or an alloy thereof. In particular, in the double-connected structure of the connecting rods 121 and 122, the connector 41 may be made of Mo, the first rod 51 may be made of KOVAR (Fe-Ni-Co alloy) material as an intermediate layer for stress buffering, and the second rod 52 may be made of Ni, etc. Also, the connecting rods 121 and 122 may be connected to the connector 41 by brazing. For example, the conductive filler 50 may be injected around the exposed portion of the connector 41 in advance, the first rod 51 may be pushed into the inside of the support eyelet 70 to bring one end surface of the first rod 51 into close contact with the connector 41, and then the first rod 51 may be heated at a high temperature and cooled to be joined, thereby electrically connecting the connector 41 and the connector 41. Next, the second conductive filler 60 is sufficiently injected into the upper part of the other end surface of the first rod 51, and one end surface of the second rod 52 is brought into close contact with the injected second conductive filler 60, and then heated to a high temperature and cooled to bond, thereby electrically connecting the two.

Although the connection portion of the connecting rods 121, 122 may be realized in this manner, in the present invention, the internal space of the shaft 120 is maintained at a vacuum lower than atmospheric pressure, thereby preventing oxidation of the connecting rods 121, 122 in the internal space of the shaft 120, so both the connector 41 and the single-rod connecting rods 121, 122 can be made of Mo.

Figure 4 is a cross-sectional view showing the connection portion of the connecting rods 121, 122 in a second embodiment of the ceramic susceptor of the present invention.

Referring to FIG. 4, the connecting rods 121 and 122 may be electrically connected to the connector 41 embedded in the insulating plate 110 so as to be electrically connected to the heating element 114 (or the electrode 112). Here, a case will be described in which the connecting rods 121 and 122 have a single rod connection structure through a support eyelet 70 coupled to a thread formed on a portion of the inner circumferential surface of a predetermined opening in the insulating plate 110.

Here, the connector 41, the connecting rods 121, 122, and the support eyelet 70 may be made of a conductive material, for example, tungsten (W), molybdenum (Mo), silver (Ag), nickel (Ni), gold (Au), niobium (Nb), titanium (Ti), or an alloy thereof.

In particular, in the present invention, since the internal space of the shaft 120 is maintained at a vacuum lower than atmospheric pressure, oxidation of the connecting rods 121 and 122 in the internal space of the shaft 120 is prevented, the connecting rods 121 and 122 can be embodied as a single rod rather than a double connection structure 51 and 52 as shown in FIG. 3, and the material of the connecting rods 121 and 122 can be made of Mo, which is the same as the material of the connector 41 electrically connected to the heating element 114 (or electrode 112) of the insulating plate 110. In other words, by making it possible to form the connecting rods 121 and 122 from a single material such as Mo without an intermediate layer 51 (KOVAR) for stress buffering as shown in FIG. 3, the electrical resistance of the connecting rods 121 and 122 can be reduced, and the occurrence of cracks or arcing due to shear stress can be reduced.

Here, the connecting rods 121 and 122 may be connected to the connector 41 by brazing. For example, the connecting rods 121 and 122 can be electrically connected by injecting conductive filler 50 around the exposed portion of the connector 41 in advance, pushing the connecting rods 121 and 122 into the inside of the support eyelet 70 to bring one end surface of the connecting rods 121 and 122 into close contact with the connector 41, and bonding the connecting rods 121 and 122 by cooling after high-temperature heating.

As described above, the ceramic susceptor 100 according to the present invention has the advantage that air pumping for substrate chucking is performed through the internal space of the shaft 120, which facilitates alignment and joining of parts, thereby improving yield and reducing processing costs. In addition, the present invention does not require the machining of through holes in the side walls of the shaft, which allows the shaft cross-sectional area to be made smaller, thereby reducing heat loss compared to the conventional technology, and since the chucking or purging function can be realized using the through passage 91 on the center side, there is no need to bend the built-in heating element or electrode to avoid the through passage on the center side, which therefore has the effect of improving temperature uniformity in zone BB around the through passage 91 compared to the conventional technology.

In addition, the connecting rods 121, 122 for supplying power to the internal space of the shaft can be formed of a single material without an intermediate layer 51 (KOVAR) for stress buffering, which reduces the electrical resistance of the connecting rods 121, 122 and reduces the occurrence of cracks or arching due to shear stress.

In addition, such a ceramic susceptor 100 according to one embodiment of the present invention may realize a vacuum chuck function using the internal space of the shaft 120, and simultaneously use an electrostatic chuck function through the electrode 112 of the chuck electrode.

As described above, the present invention has been described using specific details such as specific components, limited embodiments, and drawings. However, this is provided merely to aid in a more general understanding of the present invention, and the present invention is not limited to the above embodiments. Those with ordinary knowledge in the field to which the present invention pertains may make various modifications and variations without departing from the essential characteristics of the present invention. Therefore, the concept of the present invention should not be limited to the described embodiments, and all technical concepts that are equivalent or have equivalent modifications to the scope of the claims, as well as the scope of the claims, should be construed as being included in the scope of the present invention.

110: insulating plate 112: high frequency electrode 114: heating element 120: shaft 121, 122: connecting rod 91: first through passage 92: second through passage

Claims (12)

an insulating plate on which an electrode is disposed;
a shaft having one end connected to the insulating plate;
a power supply rod connected to the electrode and extending through the interior space of the shaft;
a separator coupled to the other end of the shaft and sealing an internal space of the shaft;
the insulating plate includes a first through passage extending between an upper surface and a lower surface thereof to communicate with an interior space of the shaft;
A ceramic susceptor performing a vacuum chuck function and/or a purge function using an internal space of the shaft in which the power supply rod is housed and the first through passage. The ceramic susceptor according to claim 1, further comprising a mount connected to the lower part of the shaft and including a second through passage that connects the interior space of the shaft to the outside. The ceramic susceptor according to claim 1, wherein the first through passage is maintained at a negative pressure lower than atmospheric pressure and a substrate placed on the insulating plate is adsorbed. The ceramic susceptor according to claim 1, which performs a purge function by maintaining a positive pressure higher than atmospheric pressure through the first through passage. The ceramic susceptor according to claim 1, wherein the electrode is a heating element and further includes a plasma generating electrode disposed in the insulating plate and spaced apart from the electrode. the insulating plate includes a second electrode spaced apart from the electrode for chucking and dechucking a substrate disposed on the insulating plate;
2. The ceramic susceptor according to claim 1, wherein the second electrode is used to chuck the substrate while simultaneously performing a purge function by maintaining a positive pressure higher than atmospheric pressure through the first through passage. a connector embedded in the insulating plate and electrically connected to the electrode,
The ceramic susceptor according to claim 1 , wherein the power supply rod is brazed to the connector with a conductive filler. The ceramic susceptor of claim 7, wherein the power supply rod extends as a single rod through the interior space of the shaft in contact with the connector and through a mount at the bottom of the shaft. The ceramic susceptor of claim 7, wherein the connector and the power supply rod are made of the same material. The ceramic susceptor according to claim 1, wherein the electrode is a heating element, an electrode for generating plasma, or a chuck electrode for electrostatic chuck function. The ceramic susceptor according to claim 1, further comprising a chuck electrode for electrostatic chuck function, the electrode being a heating element and disposed in the insulating plate at a distance from the electrode. The ceramic susceptor according to claim 1, wherein when the first through-passage is used to perform a vacuum chuck function, the electrode is further used to perform an electrostatic chuck function.